Threatened Rivers

Hydroelectric megaprojects and their impacts on the climate crisis

Marco Von Borstel from Mexico analyzes why hydroelectric megadams, far from being a “clean energy mechanism”, are fundamental pillars of the climate crisis and the global temperature rise through greenhouse gas emissions almost at the level of the aeronautics industry.

“When we put barriers in rivers, we break the water cycle, flood forest lands -which no longer absorb water- and generate a water mirror which mostly evaporates. There are studies that indicate that dams in the Amazon generate more greenhouse gases than hydrocarbon-based thermoelectric plants. But the worst change ocurrs at local level, in the destroyed territories", said the member of Otros Mundos - Friends of the Earth Chiapas.

There are only a few important rivers in Latin America that have no dams…but there are many hydroelectric dam projects, said Von Borstel, who organized the 3rd International Meeting of People Affected by Dams in 2010, in Temacapulin, two hours from Guadalajara in Jalisco State.

His analysis was part of the International Conference "Climate Change, Territories and Social Movements", that took place at the National University in El Salvador in November 2012.

The activist said that there are no examples of communities who have seen their lifestyles improve by the building of a hydroelectric dam in their territory, but on the contrary, he made reference to the first dam built in Mexico by late 19th Century, whose surrounding communities have the highest levels of cancer and kidney diseases.

Moreover, dams contribute to climate change through the emission of large amounts of methane gas, among other things, due to the decomposition of large quantities of organic matter in the bed of the dam.

Loss of biodiversity, deforestation, climate change, droughts and floods, changes in the chemical composition of water, among other issues are associated with dams.

“A large part of the problems affecting mangroves is that dams do not allow many deposits to feed those ecosystems", said Von Borstel.